Supplementary Material for "Challenges of Mining Solution Snippets from Stack Overflow: A Taxonomy to Guide Reusability"

Stack Overflow is the de-facto standard resource for seeking and finding answers for specific programming problems. Many of these answers provide code snippets. Unfortunately, it is not always easy for developers to identify a reusable code snippet that solves a specific programming problem because the provided answers on Stack Overflow often contain the solution source code along with other content such as examples of how to use the code, solutions that only apply to a very specific context, and even incorrect ways to solve the problem. In our research, we explore the nature of reusability of what we call Solution Snippets, to help developers find solutions to their problems. To that end, we conduct an empirical study to firstly understand the characteristics of questions that would typically be answered with a Solution Snippet, and secondly to understand the characteristics of Solution Snippets themselves and how they may be reused by developers. Through an exploratory study of 598 Stack Overflow answers, we: (1) identify the characteristics of questions that require a Solution Snippet to address (how-to questions); (2) identify how Solution Snippets are presented in the answers to those questions; (3) classify Solution Snippets according to their reusability into five categories; and (4) provide suggestions for the designers of Stack Overflow to improve the presentation of answers on Stack Overflow, facilitating reusability and automatic extraction.